williamjones wrote: ↑September 25th, 2021, 5:49 pm
but I cannot find this WRITTEN text in the verbal recitation.
In fact I cannot find where the verbal text
(b) comes from either.
Gimme a clue?
Thanks.
Hi William -
We discussed this in PM, where I asked how to I should handle the diagram of the two-telescope, four-prism apparatus and spectral displays given that the listener wouldn't have access to the drawings.
I said:
On the solar spectrum apparatus, there's a two-page section that includes three figures. What Helmholtz is getting across boils down to (and it would be boiling, because it's the sun, after all) is that Kirchhoff used spectral analysis to ascertain what elements there were. I've developed two versions, one which just gives the boiled-down sentence, and one where I've worked in a brief description of the apparatus. This is pages bottom of pdf 162 through most of 164.
Of the two different ways to deal with it, one was more verbose, and one simpler. You said you thought the simpler one was clearer. Here is the one you chose:
Kirchhoff’s investigation of the solar spectrum thus revealed the presence of iron, calcium, sodium, and lead.
That is presumably the text you hear that isn't on the page.
The other one, which you said you thought would be less clear for the reader/listener (though it was attempting to describe the drawings they can't see:
[Steinheil constructed for Kirchhoff an apparatus that passed a fine slice of light into one telescope, through four prisms, and into a second telescope, through which it was viewed. Kirchhoff mapped small portions of the resulting solar spectrum, and in the green, yellow, and golden-yellow portions, found iron, calcium, sodium, and lead.]
So what you're hearing is bottom of 162 through most of 164 with its apparatus diagram and three examples of Fraunhoffer's lines, replaced by the one sentence, in bold above. That's what I understood our discussion to result in. Let me know if you'd like me to handle it differently.
I'll be away April 16-22.
Voy a estar fuera el 16-22 de abril.
Cheers, VERLA